Sigmund Freud was convinced that of all the hungers and desires that motivate and drive us through life, the desire for pleasure, especially sexual pleasure, is the dominant one. There is a lot of evidence to support his view. Certainly the entertainment industry has discovered that sex sells movie tickets and raises TV ratings. And even a casual observer of human behavior is aware of the power of desire—not only sexual lust, but also that almost irresistible urge for one more piece of that …